NEW YORK — Yankees manager Joe Girardi kept his expectations for Chase Whitley Thursday simple and attainable. All he sought, Girardi explained a couple hours before Whitley made his major-league debut at Citi Field, was strikes.

The Yankees were desperate. Their starting pitching is in ruins, the product of injuries ravaging their rotation. Only Masahiro Tanaka and Hiroki Kuroda remain from their initial quintet of starters, and only Tanaka has generated enough consistency to warrant confidence every five days.

In Whitley, they were digging deep into their organizational depth chart. A third baseman at Troy University, Whitley, 24, was drafted as a reliever in the 15th round of the 2010 draft. He spent the majority of his first four professional seasons pitching out of the bullpen before the Yankees, impressed with his slider, decided to convert him to a starter permanently.

The Mets countered with their own rookie debut for the second straight night — but unlike the Whitley’s abrupt emergence, the Mets had anticipated Jacob deGrom’s rise. Twenty-four hours after top prospect Rafael Montero impressed over six innings, deGrom, a prospect drafted six rounds before Whitley, took the mound for the first time in the major leagues.

The coincidence was a rare event; the Yankees had not played a game with two starting pitchers making their major-league debuts since 1908. And an unlikely pitcher’s duel materialized. The two rookies exchanged zeroes until Whitley’s moderate pitch limit, the result of his short time as a starter, forced Yankees manager Joe Girardi to utilize his bullpen in the fifth inning.

Led by Dellin Betances’s dominant dismissal of overwhelmed Mets batters, the relief corps extended Whitley’s effort, keeping the Mets off the board over the final 4 1/3 innings in the Yankees’ 1-0 victory to conclude the 2014 Subway Series at two wins apiece.

Whitley continued Tanaka’s shutout performance from Wednesday night, limiting the Mets to two hits and two walks over 4 2/3 innings. Displaying his experience as a batter, he also slapped a single to right field in this first major-league at-bat in the second inning before he had surrendered a hit as a major-league pitcher.

“His performance was spectacular,” Girardi declared.

The Yankees (21-19) manufactured the game’s only run in the seventh inning off deGrom, aided by a shoddy defensive play. After walking Mark Teixeira, deGrom generated a potential double-play ground ball from Brian McCann.

With a shift installed, second baseman Daniel Murphy started the play with a throw to second base, where third baseman David Wright was positioned. Out of his element, Wright flicked a low throw to first baseman Lucas Duda, who could not pick it out of the dirt.

The miscue cost the Mets (19-21) immediately. Alfonso Soriano, the next batter, rocketed a line drive to the left-center field wall to score McCann from first base just ahead of high relay throw from shortstop Ruben Tejada.

From there, Betances, Adam Warren, and David Robertson bridged the Yankees’ shutout. Utilizing his lethal fastball-slurve combination, Betances struck out six of the seven hitters he faced — four looking — in 2⅓ innings.

A converted starter, Betances, 26, now boasts a 1.61 ERA and an astounding strikeout rate of 15.88 per nine innings over 22⅓ innings this season.

"I’m trying to get ahead with strike one and go from there," said Betances, who earned the win. "I can’t look for strikeouts. That’s when I get in trouble."

After accumulating 21 runs in two wins at Yankee Stadium to commence the home-and-home series, the Mets did not score a run in two losses at Citi Field. They mustered seven hits in 18 innings.

"First and foremost, you have to look at yourself in the mirror and have better at-bats," said Wright, who went 0-for-4, with three strikeouts. "But the pitching on the both sides was better in this ballpark than the first two games."

DeGrom (0-1, 1.29 ERA) was Whitley’s equivalent, at one point retiring 11 Yankees in a row and outlasting Whitley in the process en route to yielding one run over seven innings. Whitley encountered a self-inflicted predicament and a quick hook in the fifth inning. With one out, he walked Tejada and Juan Centeno, the No. 7 and 8 hitters in the Mets’ underwhelming lineup, to bring deGrom to the plate.

Two innings earlier, deGrom, a shortstop at Stetson University, registered the first hit for Mets pitching, which had entered the night a combined 0-for-64 to start the season. This time, he was asked to drop a sacrifice bunt, and accomplished the task easily to advance the runners.

The sequence coaxed Girardi from the visitors’ dugout to pull Whitley after 74 pitches. The right-hander’s career-high pitch total is 88 pitches, a number he compiled May 6, and he has accumulated more than 74 pitches in just two other outings in his minor-league career.

Girardi chose Betances and the 6-foot-8 right-hander escaped the jam by getting Eric Young Jr. to ground out. It was the least impressive of his seven outs.